Are solar tiles a worthwhile investment?

Roof mounted solar panels are an increasingly common site on buildings across the UK. Most of these systems are attached to the roof by means of a frame. However many people would prefer that solar panels were integrated seamlessly into their house’s design. The solution is the roof integrated solar panel, which fits the panel into the structure of the roof itself. The most extreme form of roof integrated panel are solar tiles, where the entire roof is made from photovoltaic materials, shaped to look just like conventional roof tiles.

So are solar tiles a worthwhile investment? Or do traditionally mounted solar cells remain the best choice?

By incorporating solar cells into the roof surface itself solar tiles effectively hide the system from view. From a distance solar tiles don’t look any different to regular roof tiles, so they are less intrusive and preserve the original look of the building. This can be good from an aesthetic standpoint, since the tiles will look just like those on other parts of the roof and on adjacent buildings. This is an advantage for older, or listed buildings and those in conservation areas. The installation of solar panels is often prohibited on such sites, but solar tiles may be allowed.

A more practical advantage is that roof integrated solar cells don’t obstruct access to the roof to the same extent as an externally mounted solar panel. Roof tiles have to be replaced and repaired from time to time, potentially more regularly than the life time of the solar cells. This means that the solar array may have to be dismantled while roof repairs take place, potentially cutting off the house’s power supply during that time.

This is not the case with roof integrated systems which are set back into the roof, so that the panels are level with the surrounding tiles. This means that they won’t interfere with reroofing activities to the same extent, although obviously care will still need to be taken not to damage the panels.

Unfortunately there are some issues with roof integrated solar panels, and solar tiles in particular. Firstly solar tiles are much more expensive than an ordinary solar array. The installation cost is also much higher, since they can only really be installed when replacing a roof entirely. This is fine when constructing a new build, but could add a large amount of expense when retrofitting an existing building.

The efficiency of solar tiles is also generally lower than for regular solar panels. This means that they won’t generate as much electricity on the day to day basis, and so will take far longer to pay back. This is exacerbated by the fact that they have to be fitted at the same angle as the roof itself. Regular panels can be set up so that they will get the most sunlight. Some can even be repositioned on a seasonal basis to get the most out of the light they receive.

This means that from a practical standpoint solar tiles are generally less effective than more traditional systems. Their main advantages are aesthetic, but as solar panels become more common this is likely to be less of a concern. Solar tiles are likely to remain a niche technology, and this will slow the rate at which their price comes down.

I've learnt the hard way that pigeons can be a nuisance and a connector was affected taking a string out.

Clearly they like the warmth of the panels so would tiling one's roof with roof solar tiles mitigate the risk?

I'm now looking into having Pigeon proof mesh installed and have 2 quotes offering different solutions. One has a patented plastic that is stuck to the underside of panels. The other is using sheet mesh(not rolled) and fitting that to the brackets/fittings and not the panel itself. The sheet mesh solution vendor said plastic goes brittle when exposed to sun/elements.

Both come with 10 year guarantees.

Which solution is tried and tested?

How long back was it known that pigeons/jackdaws would be attracted to solar panel fittings? Some business say they were set up 8-10years ago. Why was I never offered the option/advised to have mesh fitted I ask?